Gene expression profiling
A powerful too to identify and target markers associated with disease or therapy. Microarrays provide the high-throughput means to survey the range of expression changes but require validation with more sensitive independent quantitative analysis tools.

Gene cluster
A group of adjacent genes that is related or identical.

Gene conservation; genetic resources conservation
The conservation of species, populations individuals or parts of individuals, by in situ or ex situ methods, in order to provide and preserve genetic diversity.

Gene index
A listing of the number, type, label and sequence of all the genes identified within the genome of a given organism. Gene indices are created by assembling overlapping EST sequences into clusters, and then determining whether each cluster corresponds to a unique gene. The methods used to identify a cluster representing a unique gene include identification of long open reading frames (ORFs), comparison to genomic sequence, and detection of SNPs or other features in the cluster that are known to exist in the gene.

Gene insertion
The incorporation of one or more copies of a gene into a chromosome.

Gene interaction
The modification of gene action by a non-allelic gene.

Gene knockout
Inactivation of a gene by homologous recombination.

Gene library
Collection of cloned DNA fragments that contains all the genetic information of an organism. If the source of the DNA is the genomic DNA from an organism, then it is termed a genomic library. If the DNA is from cDNA made by reverse transcription of mRNA, then it is called a cDNA library. AcDNA library includes representative fragments from all genes that were being expressed at the time the RNA was isolated. Also known as gene bank; clone bank; bank.

Gene linkage
See linkage.

Gene locus
The position of gene on a chromosome that includes the flanking regulatory elements.

Gene mapping
The technique of mapping the relative positions of genes on DNA (chromosome or plasmid) and determination of the distance between genes in linkage units or physical units.

Gene modification
Chemical change in the DNA sequence of a gene.

Gene name
The official name assigned to a gene by the HUGO Gene Nomenclature Committee.

Gene ontology
A controlled vocabulary of terms related to molecular function, biological processes or cellular components that allows scientists to use consistent terminology. This was developed by the Gene Ontology Consortium.

Gene pool
The total genetic information in all the genes in a breeding population at a given time.

Gene prediction
The prediction of possible genes by a computer programme based on how well a query sequence matches with a DNA sequence of known function.

Gene probe
A single-stranded DNA or RNA sequence used to search for a particular gene or other DNA sequence. The probe has a base sequence complementary to the target sequence and will hybridise to it by base pairing. If the probe is labelled, it can be detected after subsequent separation and purification.

Gene product
The product that results from expression of a gene that may be either RNA or protein.

Gene profiling
The expression pattern of a gene.

Gene protection technology
A range of techniques used to ensure that recombinant constructs cannot be used without some regulatory policies. This is supplied by the company marketing the technology.

Gene quantification
Measurement of the amount of DNA in a smaple. This is used in mutational analysis in cancer and for expression profiling. Gene quantification can be achieved by hybridisation or PCR.

Gene recombination The presence of gene combinations in the progeny that differ from the combinations present in the parents.

Gene regulatory protein
Any protein that binds to a specific DNA sequence to alter gene expression.